LOCTITE 3611 SMT Adhesive for Surface-Mount Components and PCB Wave Soldering

LOCTITE 3611 SMT Adhesive Benefits

LOCTITE 3611 SMT Adhesive is designed for electronics manufacturers requiring rapid thermal curing and reliable component retention. Henkel recommends exposure to temperatures above 100°C, with a representative curing cycle of approximately 90 to 120 seconds at 150°C. This fast cure profile helps reduce production cycle time while supporting automated PCB assembly.

The adhesive provides very high wet strength before curing, helping resist component displacement after placement. This characteristic is particularly valuable during board transfer, oven loading and other production stages where vibration or movement could disturb small surface-mount devices.

Its very low moisture absorption supports longer exposure to humid production environments without significantly affecting dispensability or promoting void formation in the cured adhesive. Positive fluorescence under ultraviolet light also enables production teams to inspect adhesive placement and confirm coverage with compatible UV inspection equipment.

LOCTITE 3611 SMT Adhesive Applications

LOCTITE 3611 SMT Adhesive is primarily used to secure resistors, capacitors and other surface-mount components to printed circuit boards before wave soldering. Typical applications include consumer electronics, automotive control modules, industrial electronics, appliance control boards, communication devices, power supplies and general PCB manufacturing.

The product can also be evaluated for bonding other small components where controlled dispensing, fast heat curing and electrical insulation are required. Final performance depends on the component type, adhesive-dot dimensions, solder-mask chemistry, PCB surface condition and selected curing profile.

LOCTITE 3611 SMT Adhesive Technical Properties

The uncured product is a red, viscous epoxy gel with a typical specific gravity of approximately 1.3 at 25°C. Published rheological data include a yield-point range of approximately 125 to 400 Pa and a Casson viscosity range of approximately 20 to 50 Pa·s at 25°C.

After curing, representative physical properties include a glass-transition temperature of approximately 73°C, thermal conductivity of about 0.4 W/m·K and cured density of approximately 1.4 g/cm³. Published volume resistivity is approximately 2 × 10¹⁵ Ω·cm, supporting use around electrically active PCB assemblies.

When cured for five minutes at 125°C, published pull-off strength for C-1206 components on bare FR4 boards is approximately 22 to 46 N. When cured for three minutes at 150°C, push-off strength for C-1206 components is at least 30 N. These figures are typical laboratory values rather than guaranteed purchasing specifications.

How to Apply LOCTITE 3611 SMT Adhesive

After refrigerated storage, allow the unopened adhesive to reach room temperature for approximately two to four hours before use. This helps prevent moisture condensation and supports consistent dispensing. Keep dispensing nozzles, adapters, stencils and related equipment free from contamination by other adhesive residues.

For pin-transfer processing, control the adhesive bath near 25°C to 30°C and approximately 50% relative humidity. The dispensed quantity should be optimized according to pin dimensions, immersion depth, adhesive temperature and equipment configuration.

For stencil printing, Henkel recommends working near 25°C with relative humidity below 70%. The product is compatible with common open-squeegee and enclosed-head stencil systems. Printing speed, stencil design, squeegee pressure, board support and separation speed should be validated for the required adhesive-dot geometry.

Cure the assembled board using a validated thermal profile above 100°C. A typical starting condition is 90 to 120 seconds at 150°C, although total oven time must account for PCB and component heat-up. Uncured adhesive may be cleaned using suitable solvents such as isopropanol, MEK or LOCTITE SF 7360. Cured adhesive generally requires mechanical removal assisted by heat.

Why Choose LOCTITE 3611 SMT Adhesive?

LOCTITE 3611 SMT Adhesive combines fast heat curing, high wet strength, low moisture absorption, UV inspection and compatibility with pin-transfer and stencil-printing processes. It is a professional solution for high-speed SMT lines requiring dependable component retention before wave soldering.

Review the official Henkel LOCTITE 3611 Technical Data Sheet and current Safety Data Sheet before production qualification. Explore our SMT adhesives for additional PCB component bonding and wave-soldering solutions.